Several isomers of ethyl decatrienoate, other than the above-mentioned compound, are known from the prior art. They are, in fact, naturally occurring compounds which have been found in certain pear varieties [see R. K. Creveling et al., J. Agr. Food Chem. 18, 19(1970)] and references cited therein] and in grapes [see P. Schreier et al., Can. Inst. Food. Sci. Technol. J. 14, 112 (1981)]. On the other hand, J. Bricout, in Ind. Alim. Agr. 1977 277, has reported the results of an analysis of William pear brandy wherein he tentatively postulated the presence of ethyl (2E, 4Z,7Z)-2,4,7-decatrienoate as one of the components, without however having confirmed his hypothesis. Furthermore, we have not found any mention, nor even suggestion, in the cited prior art, that these pear decatrienoates and, more particularly, ethyl (2E,4Z,7Z)-2,4,7-decatrienoate, might in any way be useful in perfumery. At the most, one might have imagined that, in view of the cited references, said compounds might have been useful to confer to flavoring compositions fruity notes of the pear and/or grape type, depending on the case.